The field of the invention is that of power meter devices and the invention relates more particularly to a thermal and electromagnetic shield for a power meter device having a transparent glass or polycarbonate housing part where the device incorporates electronic components for permitting remote meter reading.
Conventional power meter devices have been extensively developed and are now achieving high efficiency and reliability over a long service life. Such devices are installed in millions of different locations including many in which the meter devices are exposed to very high temperatures and electromagnetic interference and many which are relatively remote from central power supply facilities. It has been proposed that electronic transmitter means be incorporated in such meter devices either at original installation or by retrofitting to permit remote reading of the meter devices. However many of such power meter devices have transparent glass or polycarbonate housing parts or the like to permit customer observation of device operation and to permit direct reading of visual displays provided in the existing device designs. If electronic transmitter means were to be incorporated in the existing attractive, efficient and reliable devices by retrofitting or otherwise and if electronic means were to be exposed to high temperatures and electromagnetic interference through such transparent housing parts, it would be expected that the electronic means would not provide comparable reliability and service life.